Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [voltmeter]

A voltmeter, also known as a voltage meter, is an instrument used for measuring the potential difference, or voltage, between two points in an electrical or electronic circuit. Some voltmeters are intended for use in direct current (DC) circuits; others are designed for alternating current (AC) circuits. Specialized voltmeters can measure radio frequency (RF) voltage.

Voltmeters provide a way to safely measure the voltage, or the difference in electric potential, between two points in a circuit while not changing the voltage in that circuit. The capability to measure voltage is critical to designing and maintaining advanced technology, but it also has more common and practical applications.

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What does this symbol on a voltmeter looking like an upside down U with a small line under it represent?

I decided to start a new question because I have no idea what word describes it at best, let alone to do a research (aka googling) which can be a bit inconclusive. At first glance, it looks like it convincingly represents an LED, albeit not with…
Yudhi G.
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How do we know that voltmeters are accurate?

Something that has always puzzled me is how we know the accuracy of voltmeters. From googling around, it seems that today's digital voltmeters use an ADC. An ADC works by comparing the voltage that is to be measured against a highly precise known…
John Allen
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The voltage drops measured across very high value resistors do not add up - why is that?

I have a very simple series circuit which I originally built hoping to measure voltage from an Arduino, but while calibrating realized an irregularity, so stripped it down to its basic parts. simulate this circuit – Schematic created using…
Nathan5802
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Under what conditions would using a voltmeter be more accurate than an ammeter to measure current?

Suppose you have a simple circuit with a voltage source V1 connected to a resistor R1, like this: simulate this circuit – Schematic created using CircuitLab You could connect an ammeter in series, and then the internal resistance of the ammeter…
kieransquared
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Precision notation for voltmeters

From the technical details of a multimeter: AC Voltage: - Range and Accuracy: 200mV ± (1.0%+2); 2V ± (0.7%+3); 20 ± (1.0%+3); 200/600V ± (1.2%+3) What does the notation "± (0.7%+3)" mean? Specifically, what does "+3" mean?
user31264
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Can I apply a 24v DC current to an analog voltmeter graduated between 8 and 16v for a few seconds?

I have an analog voltmeter that is used to monitor 12V batteries, with a needle going between 8V and 16V) In a specific situation, I have a series/parallel switch which turns two of my batteries into a 24V battery, and I want to make sure that this…
Brann
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Can I power and use 4 small voltmeters for 3 12v batteries in series?

I bought some small voltmeters hoping I could use them with my kid's Razor dirt bike. The bike uses 3 12v lead-acid batteries in series to provide 36 volts to the motor. Ideally, I'd like to use the voltmeters to measure total voltage of the…
KidCraftsman
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Voltage in a Short Circuit

I am very confused about voltage in short circuit. Let's suppose there is a 6 volt battery and both ends of it are connected with the same wire and it's short-circuited. Then because resistance of wire is 0 (negligible) so by the formula V=IR the…
Rajveer khajuria
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Vector Voltmeters vs Oscilloscopes?

I have come across some electronic engineering papers from the mid 1970's where they were testing tunable phase shifters. To measure the phase shift they used a vector voltmeter. As this is not a bit a kit I have come across or is as readily…
Dave
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Why is analog "voltmeter sensitivity" is defined as ohm/Volt?

What is the motivation to define a sensitivity of an analog voltmeter as ohm per voltage?
user16307
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Wiring a panel kilovoltmeter

I am planning a design for a high voltage (2.5kV) DC power supply to drive a HeNe laser. I would like to add a panel voltmeter at the power supply output to ensure it's operating correctly. I found a 0-3 kVDC analog panel meter that seems perfectly…
flashbang
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Voltmeter resolution increase by having several in series

The problem I am trying to measure quite precisely a voltage around 7.2V on a line of a PCB with a voltmeter. In this voltage range, my voltmeter only displays 3 digits. So the reading is something like 7.26V. However, I would like to have 4 digits…
Tulmandil
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How can I increase the full scale of an analog voltmeter and analog current meter or ammeter?

I have been researching about this for a long time and all I am finding is about 1mA full scale reading. I do not know what it means even. Why do we need to flow 1mA all the time? If I want to create a meter that can read 5mA, can I do some…
Obiick
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Op-amp selection for reverse polarity protection on an Arduino voltmeter

I made an accurate voltmeter using an Arduino Nano as the microcontroller. What I want now is to add a reverse polarity protection using an op-amp with a gain of 1 without changing the actual accuracy it has. In the image I show both my actual…
marcosbc
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Replacing an ammeter with voltmeter?

I have found this circuit of a millivoltmeter, and it seems like something which as a hobbyist I can do it, and the range of the measurement is very suiting one of my projects, but I would like to attach it to an Arduino interfaced precise 24 bit…
Nik Lozan
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